Fix: Bug in nonlinsolve

[shashankks0987]

References to other Issues or PRs

Fixes #21584

Brief description of what is fixed or changed

earlier, nonlinsolve([Eq(1, x + y), Eq(1, -x + y - 1), Eq(1, -x + y - 1)],x,y) raised an Attribute error
now, it returns a solution

Other comments

Release Notes

• solvers
  • Fixed a bug in nonlinsolve

[sympy-bot]

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• solvers
  • Fixed a bug in nonlinsolve (#21602 by @shashankks0987 and @smichr)

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#### References to other Issues or PRs
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Fixes #21584

#### Brief description of what is fixed or changed
earlier, nonlinsolve([Eq(1, x + y), Eq(1, -x + y - 1), Eq(1, -x + y - 1)],x,y) raised an Attribute error
now, it returns a solution

#### Other comments


#### Release Notes

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  * Added a new solver for logarithmic equations.

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* solvers
  * Fixed a bug in nonlinsolve
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Update

The release notes on the wiki have been updated.

[smichr]

you could be more specific in your changes: 'nonlinsolve recognizes Equalities that may already be true or false'